[Rhabdomyolysis: role of the nephrologist]

Rhabdomyolysis is characterized by skeletal muscle necrosis resulting in release of large amounts of toxic muscle cell components, including electrolytes, myoglobin, and other sarcoplasmic proteins into circulation. Creatinine phosphokinase (CPK) and myoglobin serum levels constitute the diagnostic hallmark. Nowadays, drugs have become one of the most frequent cause of rhabdomyolysis and acute kidney injury (AKI) is a potential life-threatening complication. The mechanisms involved in the development of AKI in rhabdomyolysis are intrarenal vasoconstriction, direct and ischemic tubule injury and tubular obstruction. According to some clinical series, the mortality rate in patients who develop AKI due to rhabdomyolysis is highly variable. The cornerstone in managing this condition is the early, aggressive repletion of fluids. The composition of replacement fluid remains controversial. Saline and sodium bicarbonate, especially in patients with metabolic acidosis, seem to be a reasonable approach. When AKI produces refractory hyperkalemia, acidosis or volume overload, renal replacement therapy is indicated.

[Vascular calcification in chronic kidney disease]

Cardiovascular risk is higher in patients with chronic kidney disease (CKD) or with End-Stage Renal Disease (ESRD) than general population because in addition to the traditional cardiovascular (CV ) risk factors, CKD patients also have others non-traditional CV risk factors linked to CKD. Among these factors, presence and progression of coronary calcifications (CAC) are considered very important in CKD or ESRD patients in recent years. A number of noninvasive imaging methods are available to detect the presence, extent and progression of CAC. In this review, we discuss the importance of CAC as non-traditional CV risk factors in CKD patients and the noninvasive methods most frequently used to assess CAC.

Prescription of oral antidiabetic drugs in K/DIGO chronic kidney disease stage 3 and 4: a single centre report

AIM

Evaluation of chronic kidney disease (CKD) is essential in order to prescribe properly oral antidiabetic drugs (OADs). The aim of our study was to report hypoglycemic drugs prescription to CKD in a cohort of type 2 diabetes mellitus (DM) outpatients.

METHODS

This survey included 1686 outpatients with type 2 DM treated with OADs who were not taking insulin evaluated by a team of diabetologists. Glomerular filtration rate (GFR) was calculated by the CKD-EPI formula and subjects were classified in the K/DIGO stages. Main clinical parameters were also evaluated.

RESULTS

Patients were aged 68±10 years, 57.1% were males, Body Mass Index was 30±5 kg/m2, glycated hemoglobin 8±1%, systolic and diastolic blood pressure values were 138±15/80±9 mmHg. Serum creatinine was 1.03±0.35 mg/dL and GFR 71±21 mL/min/1.73 m2. In 504 patients (30%) GFR was lower than 60 mL/min/1.73 m2. The different treatment groups had different GFR and hypoglycaemic drugs were prescribed differently in the different K/DIGO stages. The majority of subjects in stage 3A and 3B were treated with repaglinide, however a significant percentage of them were treated with metformin and sulfonylureas. Nearly half of subjects with CKD stage 4 were treated with metformin and sulfonylureas.

CONCLUSION

In this report we found that nearly one third of patients with type DM 2 had CKD and in a significant percentage of them OADs were prescribed even if they were in K/DIGO CKD stage 3 and 4.

Renal replacement therapy in elderly patients: peritoneal dialysis

Management of chronic uremia in elderly patients presents several clinic and organizational difficulties. Hemodialysis (HD) and chronic peritoneal dialysis (CPD) are both available for the elderly, and the choice depends on the individual, clinical and familial conditions. Several reports have compared the outcomes for older patients treated by HD or peritoneal dialysis, with those for younger or older patients undergoing peritoneal dialysis. CPD is a successful dialysis option for elderly patients, in both patient and technique survival terms. All nutritional parameters are of pivotal importance. Several barriers, such as medical and social factors, physician bias, late referral and education irrespective of the needs of older patients, influence the choice of CPD. The development of assisted peritoneal dialysis, using community-based nurses or health care assistants, can overcome some of the barriers and enable frail older patients to have home-based dialysis treatment. Increasing age is associated with higher peritonitis rates among patients who started CPD in the 1990s, while age is not associated with peritonitis in more recent CPD cohorts, and no greater frequency of adverse outcomes of peritonitis has been seen among those who began CPD after the year 2000. In elderly dialysis patients, the management of quality of life (QOL) is important as well as adequacy of dialysis, nutritional status and survival rate. To obtain a good standard of QOL, it is essential to select carers who are properly educated and who can access an adequate support system, both physical and psychological, to help them cope with their burden.

Familial interstitial nephropathy without hyperuricemia

Progressive hereditary nephropathy is described in 6 members of a single family. Renal biopsies, performed in 3 patients, revealed tubular atrophy, interstitial fibrosis, and lymphomonocytic infiltration associated with severe vascular lesions. These features were disproportionately serious when related to age, arterial pressure, and renal function. Similar familial nephropathy has been reported in the literature, generally in association with gout or asymptomatic hyperuricemia. The patients described here had normal blood concentrations of uric acid. It is proposed that the members of the present group of patients are suffering from the same interstitial nephropathy as that described in the literature and that the hyperuricemia found by other investigators is coincidental and does not play a pathogenetic role.

Clinical and radiological features of bone disease in long-term (15 or more years) hemodialysis patients

Fifteen patients on regular dialytic treatment for more than 15 years were given X-rays of the skull, spine, shoulders, wrists, pelvis and knees with the purpose of studying the principal skeletal and articular alterations due or not due to the uraemic status. Serum calcium, phosphorus, parathyroid hormone, alkaline phosphatase and basal aluminium were recorded. Osteopenia was evident in all the patients. Ten of whom (67%) showed alterations due to hyperparathyroidism. Nine patients presented the marks of dialysis spondyloarthropathy; in 14/15 cases geodes were present in the wrists, humeral heads or hip-joints; in ten patients there were multiple amyloid lesions. Two patients with serum basal aluminum above 100 micrograms/L showed the typical radiographic marks of osteomalacia. The majority of the long-term survivors showed multifactorial osteo-articular alterations resulting mainly from the combination of hyperparathyroidism and dialysis-related amyloidosis. The less frequent joint alterations were represented by arthrosis, enthesopathy and chondrocalcinosis. Disability and decreased articular mobility resulted in being mainly due to amyloid osteo-arthropathy.

Histological features of non-A, non-B hepatitis in hemodialysis patients

In 12 hemodialysis (HD) patients with persistently raised serum alanine amino-transferase concentrations, 6 of which with anti-HCV antibodies, a liver biopsy was performed. The histological examination showed chronic persistent hepatitis or less significant changes in 11 patients and mild chronic active hepatitis in only 1. Non-A, non-B hepatitis seems to demonstrate in HD patients a low tendency to induce an active and progressive liver disease.

[Radiology of osteoarticular changes in patients undergoing periodic hemodialysis for more than 15 years]

Osteoarticular complications, which are characterized by osseous pain, pathologic fractures, and decreased articular mobility, represent one of the major problems affecting long-term (over 15 years) hemodialysis patients. These changes seem to have a multifactorial etiology; they include osteomalacia, secondary hyperparathyroidism, and dialysis-related amyloidosis. Ten patients (5 males and 5 females, mean age 55 +/- 7 years) on long-term (over 15 years) hemodialysis were submitted to X-ray examinations of the skull, spine, shoulders, wrists, pelvis, and knees. Serum calcium, phosphorous, parathyroid hormone, alkaline phosphatase, and basal aluminium levels were also calculated. Osteopenia was demonstrated in all patients. Seven of them had alterations due to hyperparathyroidism. Six patients exhibited signs related to dialysis spondyloarthropathy; in 9 cases amyloid lesions, geodes, and erosions were present in wrists, humeral heads, or hips. One patient exhibited osteomalacic changes. Most long-term dialysis patients presented multifactorial osteoarticular changes due to hyperparathyroidism, osteomalacia, and dialysis-related amyloidosis. Clinical symptoms and decreased articular mobility appeared to be due mainly to amyloid osteoarthropathy.

Henoch-Schönlein purpura after Salmonella hirschfeldii infection

The authors present a case of Henoch-Schönlein purpura in a young soldier (19 years old) which they consider important for its etiology and the length of its oligoanuric phase. The syndrome followed a Salmonella hirschfeldii infection, and a protracted oligoanuric phase was followed by nephrotic syndrome and selective glomerular proteinuria which lasted for 1 year. The young man recovered after the eradication of the Salmonella. It seems possible that there was an overall anomalous regulation of the 'lymphoid system of the mucosa', perhaps dependent on a genetic predisposition.

Radiological features of dialysis amyloid spondyloarthropathy

Nine patients undergoing regular dialytic treatment (RDT) for more than 60 months (mean 125 +/- 33 months) showed clinical and radiological evidence of non-infective destructive spondyloarthropathy (DSA). The cervical spine was the skeletal segment most affected (100% of cases). Three patients were found also to be suffering from discal and bone alterations of the dorsal column, and in two other patients the vertebral bodies L4-L5 were changed. Typical radiological pictures showed a narrowing of intervertebral spaces with the destruction or sclerosis of adjacent subchondral bones, erosions of vertebral body plates and cavitations. CT studies of the altered spines confirmed discal lesions and osteolytic areas with bone condensation at each level. Ligamentous lesions resulting in severe disorders of spinal statics were discovered during autopsy of three patients. Histological study of disc and peridiscal ligaments indicated the presence of large amyloid deposits containing beta-2-microglobulin (B2-m). It is possible that the minor biocompatibility of the cuprophan membrane of dialyzers is the most significant factor responsible for the hyperproduction of B2-m and thus of the osteo-articular deposition of a new type of amyloidosis.

[Behavior and significance of phalangeal bone changes in uremic patients under periodic hemodialysis treatment]

Bone damage in hand phalanges has been evaluated with reference to age and duration of hemodialysis (on the basis of 248 radiological observations), in 93 cases with chronic renal failure (age: 20-59 years). These patients were on regular dialytic treatment (RDT) from 1 to 138 months. 72% of the patients underwent several periodic (annual) controls using the mammographic technique. The radiologic evaluations have been arranged into groups according to age. Skeletal damage was more evident when RDT was prolonged. Bone damage increases with age in the first 48 months; afterwards, on the contrary, bone changes were more evident in middle aged patients. At the beginning of RDT, acroosteolysis was the most important change always present. Both subperiosteal and intracortical resorption are more evident increasing age and duration of RDT. Radiological changes give a clear picture of the possible histo-morphologic pattern that characterizes uremic osteodystrophy.